Machine for the manufacture of filled and sealed containers

ABSTRACT

A machine for the manufacture of essentially boxlike packing containers wherein a first continuous web of a foldable material is drawn from a supply roll and folded to establish a series of connected U-shaped sections which are received in moulds, and wherein a second continuous web of a foldable material likewise drawn from a supply roll and folded into a U-shaped configuration is joined to the series of U-shaped sections established by the first web in such manner as to complete the wall structure of the container. Filling takes place prior to completion of sealing of the two webs to one another and thereafter the string of formed, filled and sealed containers are separated by a cutting action between the sections.

United States Patent 1191 Stark et al.

MACHINE FOR THE MANUFACTURE OF FILLED AND SEALED CONTAINERS Inventors:Sven Olof Soren Stark, Rydsgard;

Jan-Erik Olsen, Lund; Franz Soukup, Malmo, all of Sweden Tetra PakDevelopment SA, Lausanne, Switzerland Filed: Jan. 16, 1974 Appl. No:433,789

Assignee:

Foreign Application Priority Data Jan. 18, 1973 Switzerland 696/73 Nov.11, 1975 3,287,878 11/1966 Mobley 53/133 3,325,961 6/1967 Lindh et al.53/180 x 3,726,058 4/1973 Stark 53/29 Primary E,\'amitlerRobert L.Spruill Attorney, Agent, or Finn-Pierce, Scheffler & Parker ABSTRACT Amachine for the manufacture of essentially boxlike packing containerswherein a first continuous web of a foldable material is drawn from asupply roll and folded to establish a series of connected U-shapedsections which are received in moulds, and wherein a second continuousweb of a foldable material likewise drawn from a supply roll and foldedinto a U-shaped configuration is joined to the series of U-shapedsections established by the first web in such manner as to complete thewall structure of the container. Filling takes place prior to completionof sealing of the two webs to one another and thereafter the string offormed, filled and sealed containers are separated by a cutting actionbetween the sections.

2-1Claims, 19 Drawing Figures US. Patent Nov. 11, 1975 Sheet1of153,918,237

U.S. Patent Nov. 11, 1975 Sheet 2 of 15 3,918,237

US. Patent Nov. 11,1975 Sheet3of 15 3,918,237

US. Patent Nov. 11, 1975 Sheet4 of 15 3,918,237

US. Patent Nov. 11, 1975 Sheet 5 of 15 3,918,237

US. Patent Nov. 11,1975 Sheet60f 15 3,918,237

U.S. Patent N0v.11,1975 Sheet7of 15 3,918,237

U.S. Patent Nov.11',1975 Sheet80f 15 3,918,237

U.S. Patent Nov. 11,1975 Sheet 9 of 15 3,918,237

RN A RN QwN www RN .8 gm RN U.S. Patant Nov; 11,1975 Sheet 10 of 153,918,237

US. Patent Nov. 11,1975 Sheet110f15 3,918,237

US. Patent Nov. 11, 1975 Sheet 12 of 15 3,918,237

U.S. Patnt Nov. 11, 1975 Sheet 13 of 15 3,918,237

US. Patent N0v.11, 1975 Sheet 14 of 15 3,918,237

hlllllllllll US. Patent Nov. 11,1975 Sheet 15 of 15 3,918,237

ig. 72b

MACHINE FOR THE MANUFACTURE OF FILLED AND SEALED CONTAINERS The presentinvention relates to a machine for the manufacture of packingcontainers, comprising a device for the forming of a first continuousweb of a foldable material to a series of connected, U-shaped sectionsthrough folding of the web, a device for the joining of a second web offoldable material to the said first web, a device for folding down theedge zones of the said second web to lie against the edges of the foldedfirst web, a device for sealing the joined portions of the said secondweb and the said first web along the common contact surfaces of the websfor the formation of a series of parallelepipedic cavities, and finallya device for filling the said cavities with the intended goods.

Frequently, during the packing of goods, the packing containersthemselves are manufactured at the same time as the goods intended forpacking are supplied to the packing containers. This can be done whenthe packing containers consist of blanks with punched out lugsmanufactured in advance, which is an automatic assembling machine, arefolded together to form a container, or when the packing material isfurnished in the form of a web, which, e.g., is folded over into a tube,the longitudinal edges of which are sealed to one another, whereupon thetube is filled with the goods and is then divided by means of successivetransverse sealings in areas at right angles to the tube axis. Thepieces of tube divided in this manner can then be subjected to a formingprocess so that they are given, for example, a lasting parallelepipedicshape.

With the abovementioned methods for the manufacture of packages there isan unavoidable waste, in that a part of the packing material becomesembodied in the flap fastening arrangement or other parts which do notdirectly form a part of the packing body. If, e.g., a piece of a tubewhich has been sealed off at right angles to the tube axis is mouldedinto a parallelepipedic shape, a triangular double-walled flap isproduced at each corner which requires packing material which does notdirectly constitute any part of the packing container itself, and isinefficiently used.

It has been found in practice that the continuous manufacture of packingcontainers from a web is to be preferred to the manufacture of packingcontainers from blanks made in advance, and the main reason for this isthat the weblike packing material can be supplied in rolls, where thesurface of the packing material web lies well-protected between adjacentturns in the roll, whereas, by contrast, prefabricated blanks cannot beprotected in the same manner. Furthermore, the packing material which issupplied in a roll takes up considerably less space and is easier totransport than the kind of packing material which is supplied in theform of prefabricated blanks and the compact packing material rollsrequire moreover less outer wrapping during transport, which as a greateconomic advantage.

As mentioned before an undesirable waste arises, however, if for exampleparallelepipedic packages are formed of a web which is folded over intoa tube, and it is an object of this invention to reduce this waste asmuch as possible. The machine in accordance with the present inventionshows an arrangement for the manufacture of packing containers from aweb of packing material with a minimum of packing mate rial waste andthe machine in accordance with the invention is characterized by adevice for the folding of a first packing material web, which devicecomprises moulds over which the web is adapted to be shaped, a number ofthe said moulds being arranged behind one another and being arrangedmovable in the direction of advance of the first web, and that thedevice for the joining of a second packing material web to the first webcomprises a driven feeder drum, which is adapted to impart to the saidsecond web a feed movement which is synchro nous with the movement ofthe said moulds. The invention is characterized further in that thedevice for the forming of the said first web comprises an endless seriesof moulds arranged one behind another, which are adapted to move withconstant speed and a forming tool rotatable about an axis comprising oneor more curved forming surfaces, which are adapted to press the saidfirst web down into the said moulds with the object of bringing the webinto contact with the walls of the moulds and thus to impart to the weba shape which corresponds to the surfaces of the moulds.

In the following will be described an embodiment of the packing machinein accordance with the invention with reference to the drawings, whichare partly of a schematic character and for the sake of clarity the samedetails have been given the same reference numbers in all the figures.

The drawing comprises the following figures:

FIG. 1 shows schematically a total front view of the machine FIG. 2shows schematically the driving of the machine FIG. 3a and 3b show thedriving equipment of the forming tool,

FIGS. 4a-4c show the forming operation at the folding of the one packingmaterial web,

FIG. 5 shows a front view of the feeder drum,

FIG. 6 shows a side view of a partly cross-sectionalized feeder drum,

FIG. 7 shows a driving equipment of the feeder drum FIG. 8 shows aperspective view of the equipment for the assemblingof the packingmaterial webs and the sealing of theedge zone flaps, folded down, of thesecond packing material web to the folded side edges of the packingmaterial web,

FIG. 9 shows a device for the sealing of the central part of the secondpacking material web to the tops of the folded packing mate rial web,together with a device for the separation of the sealed, individualpacking units,

FIG. 10 shows a front view of the parts of the machine, by means ofwhich the webs of packing material are assembled and sealed to oneanother,

FIG. 11 shows a perspective view of the driving equipment for the set-upshown in FIG. 10,

FIG. 12a shows a series of connected packing containers which have beenmanufactured by the machine in accordance with the invention, and

FIG. 12b shows a separated individual packing container.

Although it is possible to use as packing materials various materials ormaterial combinations, such as, e.g., plastic film, paper coated withplastic, metal foil coated with plastic and paper or other combinationsof known material which can be laminated to one another, it is assumedin the following description that the packing material consists of a webof foamed plastic material, for example polystyrene foam which at leaston the one side has a layer of a homogeneous plastic material, e.g.,polystyrene. The two packing material webs which after forming areassembled and sealed to one another need not necessarily be of the samethickness, but for the sake of simplicity it shall be assumed in thepresent case, that the packing material webs are of 5 GENERALDESCRIPTION OF THE MACHINE In FIG. 1 is shown a front view of a packingmachine in accordance with the invention, the frame for the packingmachine proper being designated 1, a device for the machining andfinishing of the packing units manufactured being designated 33, anautomatic packaging device 35 and a packing material part 58.

The packing material part 58 comprises a number of so-called rollerstands comprising magazine rolls of packing material. The rolls 8 and 9comprise packing material webs, which in the case described here consistin particular of extruded foamed plastic webs of polystyrene material,which is lined on both sides with layers of homogeneous polystyrene. Thepacking material webs 5 and 6 are rolled off the magazine rolls 8 and 9,and are passed over the guide rolls 25. The magazine roll 10 containsstrip material 7 of homogeneous plastic material, which strip material 7is intended to be used for the bringing about of an opening on thepackages manufactured.

The packing machine proper consists, as mentioned above, of a frame 1,which frame supports a rotatable drum 23 which is adapted so that thepacking material web 6 can be passed over it and on which workoperations are carried out at stations along the periphery of the drum,which in the case shown here is divided into 12 sections. The packingmachine comprises further a device 2 for the forming of the web 5. Thedevice 2 comprises movable moulds 4 which are fitted onto an endlesschain, which in the figure shown moves in clockwise direction. Thedevice 2 further comprises a forming tool 3, which is designed as arotatable double section vane, by means of which the packing materialweb 5 is brought into contact with the moulds 4 to form a series ofconnected U-shaped sections. In FIG. 1, furthermore, a supply line forthe goods to be filled into the containers is designated 20, a controlvalve for the control of the quantity of goods supplied is 21 and afilling tube 19. A heating device is designated 15 and a supply line forhot air 22. A reciprocating, movable column is designated 13 and abearing which is integral with the machine frame 1 for the guiding ofthe column 13 is designated 14. The column 13 supports a folding tool16, a sealing element 17 and a cutting element 18 which all movetogether with the column in its reciprocating movement which is adjustedso that the column moves synchronously with the moulds 4 in its downwardmovement, whilst the upward return movement is quicker.

The finished formed packages are transferred from the forming moulds 4of the forming device 2 to the finishing device 33 by means of aconveyer belt 28 which runs between two end rolls 29 and a transportwheel 27 arranged in between.

In the finishing device 33 projecting sealing fins are removed ormachined so as to impart to the packages 30 a more pleasing appearanceand free them from edges which might interfere with each other duringtransport and handling. The packages 30 are retained in the endlesschain of the finishing device, which comprises projecting parts whichform between them spaces within which the packages 30 can beaccomodated, with the help of a supporting belt 31 which runs around anend roll 32 and one of the earlier mentioned end rolls 29. The machiningis carried out with the help of the machining tool 36, and the packages30 are finally delivered by means of a device 34 to an automaticpackaging device 35 where the packages are put down into transportcartons or transport baskets for distribution.

The function of the packing machine is as follows:

From the magazine roll 8 a first packing material web 5 is rolled off,which is passed over a guide roll 25. The packing material web 5 isrolled off with the help of a drive pulley 24 which is controlled withthe help of a photo-cell equipment containing two photo-cell devices ll.If too much packing material web 5 has been rolled off by means of thedrive pulley 24, the loop of packing material web formed will cover, asshown in FIG. 1, the lower one of the photo-cell devices 11. If thishappens, the governor obtains an impulse and the driving device for thedrive pulley 24 is stopped. The supply of packing material is then alsostopped, the loop of packing material diminishes and when the loop hasbecome so small that it clears the photocell device 11, the feed ofpacking material is started again with the help of drive pulley 24. Thepacking material web 5 is brought into contact with the moulds 4 on theforming device 2, in which the moulds 4 are fitted on an endless chain,which moves at constant speed in a closed track. The packing materialweb 5 is brought into contact with the moulds 4 with the help of aforming tool 3, which consists of a rotatable and pivotable doublesection vane, the function of which will be described in detail in thespecial machine description. With the help of the forming tool 3 thepacking material web 5 is brought accurately into contact with themoulds 4 whilst the web 5 is folded to form an endless series ofU-shaped parts, which with the help of the forming device 2 are mademainly to move downwards at a constant speed.

The second packing material web 6 is rolled off its magazine roll 9 andis passed over a guide roll 26 and is then brought into contact withfeeder drum 23. The feeder drum 23, as mentioned earlier, has 12 formingsurfaces each with a width which largely corresponds to the distancebetween two successive moulds 4 on the forming device 2. The feeder drum23 rotates at constant speed whilst an outer ring or oscillator plate 59moves in a reciprocating rotatory movement around the drum 23. The plate59 carries machining devices such as a hole punch and cover stripapplicator 60, forming and cutting element 61 and heating device 62.When the web 6 with the help of the feeder drum 23 is moved past themachining stations 60,61 and 62 a punching of pouring holes, applicationof cover strip over the pouring hole, heating up of the web and possiblythermoforming of the web is carried out, as well as cutting of edgezones of the web at right angles to the longitudinal direction of theweb. From the magazine roll a strip 7 of homogeneous plastic material isrolled off, which strip is placed by means of the cover strip applicator60 over the pouring hole produced in the web 6 and is fixed to the web6, so that the pouring hole is sealed. Furthermore, by means of thecover strip applicator, the front part of the strip 7 is cut off so thatthe cover strip applied over the pouring hole produced is severed fromthe rest of the strip 7. The web 6 provided with pouring opening andopening device, is also provided with slits at the edges of the web, thesaid slits extending at right angles to the longitudinal direction ofthe web 6, to a length largely corresponding to the height of the moulds4, and is then advanced with the help of the feeder drum 23 at aspeed'which is the same as the speed of movement of the moulds 4, theweb 6 being advanced until its central part'is placed over the tops ofthe moulds 4, whilst the slotted portions of the web edges projectbeyond the moulds 4. By means of a governor, not shown here, the web 6is advanced with the help of the feeder drum 23 in such a manner, thatthe slits in the web 6will be positioned right in frontof the uprightpartitions of the moulds 4.

While the web 6, with the help of the feeder drum 23, is advancedsynchronously with the movement of the moulds 4, the column 13 attainsits upper end position and starts a downward movement, and issynchronous with the movement of the [moulds 4. The column 13 carries aheating device 15 which canbe connected via a pipeline 22 to an airsource, and by means of the heating device' 15 hot air is blown throughthe holes, which are provided in a specified pattern, against theunderside of the edge zones of the web 6, which are delimited by thesaid slits in the edge portions of the web, the plastic material beingsoftened and activated for sealing, and at the same time the edge zonesof, the web 5 are also heated up by the blowing of hot air against theedge zones of the web 5 exposed at the lateral edges of the moulds.

At the same time as the heating up of the zones on the webs 5 and 6,which are intended to be sealed to one another, is carried out with thehelp of the heating device 15, the flaps formed between the slits in theweb 6 are folded down, with the help of folding flaps 16, against thesides of the moulds 4 and, as a result of this, join together the edgezones of the parts of web 6 and the edge zones of the parts of web 5,which, in an earlier working phase, had been heated with the help of theheating device 15 to such a degree, that the joined portions of the websare fused together to form a mechanically durable and permanent sealwhich is stabilized by the folding tool 16 which cools down the sealingarea during the time when it is in contact with the folded down portionsof the web6. When the webs 5 and 6 have been joinedtogether throughlateral sealings in the aforementioned manner, the' goods to be filledinto the containers are supplied through the filling pipe 19, which isarranged between the web 6 and above the tops of the .moulds 4, thebox-like spaces formed underneath the web 6 being filled with theintended goods. The filled box-like spaces aresealed off with thehelp'of the sealing element 17 to form closed units, in that the web 6is sealed to the parts of the web 5 which are situated above the tops ofthe upright portions of the moulds 4. The sealing element 17 is alsofixed to the column 13 and follows the column in its reciprocatingmovement, which means that the sealing takes place while the columnmoves downwards synchronously with the moulds 4. In the case shown herethe sealing element is of the ultrasonic type, but it is also possibleto use heat sealing devices of the conventional type. The closed unitsformed are finally separated from one another with the help of thecutting element 18, which severs the closed units from one another bymeans of a cut through the sealing zones which have been accomplished bymeans of the sealing elements 17.

The filled and closed packing units 30are retained in the moulds withthe help of a conveyor belt 28 arranged underneath the forming device,which runs between two end rolls 29, and the packing units 30 aretransported by means of a transport wheel 27 provided with projectingvanes to theraforementioned machining device, where any projectingsealing edges are machined by means of a machining element 36, where.-upon the packagesare finally passed bymeans of the element 34 to anautomatic packing device 35, where the packages 30 are put down intocartons or transport boxes.

The packing machine can be operated by means of a control and actuatingpanel 12, containing the necessary actuating devices as well as controlinstruments to indicate the temperature in the various heating zones,

fitC.

The driving of the packing machine is illustrated in FIG. 2, where themain, motor is designated 37 and a driving gear coupled to the mainmotor is marked 38. The output gear 39 of the driving gear 38 is in meshwith an intermediate wheel 40 which transmits the driving force of themotor to a gear 41, which is fitted to'the same shaft 49 as a V-beltpulley or serrated belt pulley 43, which shaft is at the same time thedriving shaft for the forming device 2 and the chain carrying the moulds4. By means of the V-belt pulley or serrated belt pulley 42 a movementis transmitted via the V-belt or serrated belt 43 to the intermediatewheel 44 which is fitted on ashaft 48. On the shaft 48 is a further'beltpulley, which via serrated belt or V-belt 45 transmits a movement to thebelt pulley 46 which is fitted to a shaft 47 by means of which thefeeder drum 23 is driven.

, The gear 41 mentioned earlier, further drives the gear 57 which isfitted to a shaft 50, on which shaft the transmission wheel 27ismounted; the gear 57 further drivesa wheel 56 which in turn is fitted toa shaft 51, by means of which the finishing device 33 is driven. On theshaft 51 is fitted further a larger gear 55 which is in mesh with asmaller gear 54 which via a sprocket wheel with locking mechanism drivesa chain 53 from an auxiliary motor 52. The smaller gear 56 is fitted tothe shaft 51 which via a locking mechanism is connected to the shaft 50.I

When the driving motor 37 drives the machine, the movement istransmitted via gears 39,40,41 and 57 to the gear 56, which via thelocking mechanism transmits the movement to the shaft 51. The auxiliarymotor 52 is then cut out and the chain 53 is immovable owing to alocking mechanism in the sprocket wheel on the same shaft as the gear54. When the driving motor 37 has stopped,- the auxiliary motor 52 canbe started and this can then drive the finishing device 33 via thesprocket wheelwith locking mechanism of the chain 53, the gear 54, thegear- 55 and shaft 51. The locking mechanism between the shaft 51 andthe gear 56 disconnects then the shaft 51 from the gear 56. The reasonfor this set-up is that it should be possible to drive the finishingequipment 33 when the packing machine is not in operation.

In FIG. 12a is shown partly in cross-section a picture of a series ofmutually connected packing containers as they appear when they areaccomodated in the moulds 4 of the forming device 2, and as can be seenfrom FIG. 12a, the connected series of packing containers 30 are formedof the web 5 folded into U-shaped sections and of the web 6 which isslotted along its edge zones with the slits 63 to form the flaps 64,which are folded towards the ends of the U-shaped sections formed fromthe web 5 and sealed to these by device 15. Furthermore, the tops of thefolded web 5 arae sealed by device 17 to the central portion of the web6 along the sealing zone 65 after filling. With the help of a cutthrough the sealing zones 65 individual containers of the type as shownin FIG. 12b are separated and, as can be seen from that figure, thecontainer consists of two U-shaped elements which are formed by the webs5 and 6, and which are sealed to one another along the areas where theyare brought into contact with one another.

A row of interconnected packing containers in accordance with FIG. 12acannot be manufactured by means of the packing machine described hereunless the cutting elements 18 for separation of the packing containersare removed or put out of gear, and this is easily made possible incases where a row of interconnected packing containers is desired. Thecutting elements 18 can also be placed in such a way that they separatea number of interconnected packing containers, e.g., 2 and 2 or 5 and 5.

After this general introduction to the machine, special details anddevices of the packing machine in accordance with FIG. 1 will bedescribed more closely in a special part of machine description.

SPECIAL MACHINE DESCRIPTION I. Folding device In FIGS. 4a-4f is shownthe fold-forming procedure of the packing material web 5, which with thehelp of the forming device 2 (FIG. 1) is formed into a series ofconnected U-shaped elements. The forming takes place in such a mannerthat the web 5, which can be provided with crease lines facilitating thefold formation which have been arranged in advance, is brought intocontact with the moulds 4, which are hingeably connected to one anotherto form an endless chain. Each mould 4, as can be seen from FIG. 4a, mayconsist of an L-shaped link with an upright part 66 and a bottom part67. The chain formed by the moulds 4 is guided and driven by means ofdriving wheels, and the shaft of the upper wheel is designated 48. Themoulds 4 can be provided advantageously with guide rolls which areadapted so that they run in fixed guiding tracks, which are arrangedalong the course of movement of the forming equipment.

By means of the driving shaft 49 (FIG. 2), which in a manner describedearlier is coupled to a driving motor, the chain formed by the moulds 4is moved around at a preferably uniform speed in the direction of thearrow. The packing material web 5, which is to be folded, is broughtinto contact with the moulds 4 by means of a rotatable forming tool 3,which consists of two vanelike parts 68 which are rotatable about anaxle 104. The axle 104 in its turn is fitted to a reciprocatinglymovable pendulum arm, the driving of which will be described in detaillater. The vanelike parts which in the present case are two in number,have each a curved 8 side-rolling surface 125 and a curved end-rollingsurface 124.

The forming procedure in such that the chain of moulds 4 moves at apreferably uniform speed in the direction of the arrow and that the saidpendulum arm imparts to the axle 104 of the forming tool a movementlargely synchronous with the moulds. In FIG. 4a is shown how the axle104, which carries the vanelike parts 68, rolls over the upper endsurface of the upright part 66 of the mould 4 at the same time as theaxle 104 moves clockwise synchronously with the mould 4. At the rotationof the axle 104 and the vanelike parts 68 of the forming tool 3 alsorotate and the web 5 is passed down into the following mould.

In FIG. 4b is shown the forming procedure a little later, and in FIG. 40the vane 68 of the forming tool 3 has almost placed the web 5 into thecorner point 69 of the mould 4. When, as shown in FIG. 4d the vane 68has guided the web 5 into the corner 69, the said pendulum arm commencesa return movement at the same time as contact between the axle 104 andthe upper end surface 70 of the mould 4 is broken. While the pendulumarm and the forming tool 3 are moved opposite the direction of movementof the moulds, the end surface 124 of one of the vanes 68 of the formingtool 3 is made to press by means of a skid-free rolling movement, theweb 5 against the bottom part 67 of the mould 4.

In FIG. 4e the edge of the vane 68 has reached the far edge on thebottom part 67, whereupon the web 5, by means of the curved rollingsurface 125 of the vane 68, is successively brought into contact againstthe front edge, in the direction of movement, of the mould coming nextin the series of moulds. In FIG. 4f the whole rolling surface of thevane has rolled over the front edge of the said mould 4 and the axle 104has just been brought into contact with the upper end surface 70 of themould, over which the axle 104 is adapted to roll whilst the web 5 atthe same time is pressed against the end surface 70. In the positionaccording to FIG. 4f the axle 104 is given once more by means of itspendulum arm a movement which is synchronous with the movement of themoulds 4 and the position as shown in FIG. 4a is obtained.

In the foregoing a complete cycle has been described which is repeatedover and over whilst the web is brought into contact with the moulds 4.It was found that the packing material owing to its rigidity remains inthe applied position, so that the contact with the forming surfaces ofthe moulds is substantially unbroken, which is a pre-condition for asuccessful forming operation.

Since the web 5 can advantageously be provided with a printed text orornament of an advertising or informative nature it is important thatthe fold formation of the web 5 should take place in register with theprint. It was found that pre-printed packing material webs, 5, which areprovided with crease lines facilitating the fold formation can readilykeep the ornament in register with the U-shaped sections, since thefolding takes place along the crease lines, which are arranged inadvance in register with the ornaments. When webs 5 of packing materialwhich do not have crease lines are used it is necessary to adjust thefeed of the web so that it agrees with the printed ornament, and in thenormal manner the monitoring of the position of the ornaments inrelation to the U-shaped sections takes place with the help ofphoto-cell devices not shown here, which are adapted so as to monitorindices applied to the packing

1. A machine for producing filled, sealed packages comprising means forprogressively and continuously folding a first continuous web ofpackaging material into a series of successive, interconnected U-shapedsections extending transversely of the length of the web, feeder drummeans for progressively slitting a second web of packaging materialtransversely at the edges thereof in synchronism with the means forfolding the first web, to provide a series of longitudinal opposedmarginal flaps therealong, means for folding and sealing said flaps tothe outer side edges of the U- shaped sections of the first web to formpackage cavities, means for filling said package cavities with a fillingmaterial, and means for sealing the filled packages by sealing thesecond web to the transverse ends of the legs of the U-shaped sectionsof the first web along lines transversely of the second web andcoextensively with the slits between the flaps so as to form filled,sealed packages, said means for forming the U-shaped sections in thefirst web comprising an interconnected series of U-shaped moulds movablein the direction of movement of said first web and means forprogressively folding said first web into said moulds during movement ofsaid first web to form the Ushaped sections.
 2. A machine as claimed inclaim 1 wherein said means for progressively folding the first web intosaid moulds comprises a rotatable axle and at least one forming elementmounted on said axle for rotation therewith and having forming surfacesfor progressively and continuously pressing said first web down intoeach successive mould of the series during rotation of said formingelement to contact said first web and press it against the walls of eachsuccessive mould.
 3. A machine as claimed in claim 2 wherein said atleast one rotatable forming element includes two elements each havingcurved forming surfaces, said two elements being disposed ondiametrically opposite sides of said axle.
 4. A machine as claimed inclaim 3 and further comprising a reciprocating swivel arm, saidrotatable axle being mounted on said arm for providing said axle andsaid forming elements with a reciprocating movement laterally of saidaxle during a portion of the rotation thereof.
 5. A machine as claimedin claim 4 and further comprising a cam disk for imparting reciprocatingmovement to said swivel arm.
 6. A machine as claimed in claim 5 andfurther comprising means for temporarily accelerating the reciprocatingmovement of said swivel arm to feed increased portions of said first webto said moulds to reestablish proper feed of the first web whenunderfeeding occurs.
 7. A machine as claimed in claim 4 wherein saidaxle frictionally engages the first web as the web passes over the endsof the legs of each U-shaped mould to cause rotation of said formingelements to press said first web progressively in to each successivemould.
 8. A machine as claimed in claim 7 wherein said axle continues toengage the first web until said rotating forming element reaches thebottom of the U-shaped mould to press the web against the bottom of saidmould.
 9. A machine as claimed in claim 8 wherein said reciprocatingswivel arm moves said axle and said forming elements in a directionopposite to the movement of said moulds while one of said formingelements passes across the bottom of each mould whereby the axle onwhich said forming elements are mounted engages the first web as itpasses over the end of the succeeding U-shaped mould and is rotated toretract the one forming element from the bottom of the preceeding mould.10. A machine as claimed in claim 1 wherein said series of mouldscomprises a series of L-shaped links, the end of one leg of eachL-shaped link being rotatably connected to the angular corner portion ofan adjacent link to form an endless chain of moulds.
 11. A machine asclaimed in claim 10 wherein said L-shaped links are provided with guiderolls and said machine further comprises guide tracks for receiving saidguide rolls for always positioning the projecting leg of said L-shapedlinks perpendicular to the direction of movement of said endless chainof moulds.
 12. A machine as claimed in claim 1 wherein said feeder drummeans includes a drum having a plurality of equal, relatively flatsegmental surfaces about the periphery thereof for carrying said secondweb, said segmental surfaces having a width corresponding to the spacingof the moulds and a length corresponding substantially to the length ofthe moulds, said segmental surfaces also haviNg outer portions having alength corresponding to the height of said moulds.
 13. A machine asclaimed in claim 12 and further comprising a reciprocable elementrotatably surrounding said feeder drum means and means for causing saidreciprocable element to rotate with said feeder drum means and return toits former position.
 14. A machine as claimed in claim 13 and furthercomprising means opposite one segmental surface and mounted on saidreciprocable element for forming the slits at spaced locations along theside edges of said second web to form said longitudinal opposed marginalflaps therealong.
 15. A machine as claimed in claim 14 and furthercomprising a plurality of separate means opposite other segmentalsurfaces and mounted on said reciprocable element for punching holes insaid second web to serve as pouring openings and for subsequentlyapplying a removable cover for said openings and for thermoforming saidsecond web.
 16. A machine as claimed in claim 15 and further comprisingmeans for actuating said slit forming means and said plurality ofseparate means while said reciprocable element rotates with said feederdrum means.
 17. A machine as claimed in claim 12 and further comprisingmeans disposed between the segmental surfaces for radial displacementthereof with respect to said drum to increase or decrease the peripheralsurface of said drum so as to increase or decrease the length of thesecond web being processed by said feeder drum means to maintainsynchronous feed of the second web with respect to the first web.
 18. Amachine as claimed in claim 17 and further comprising conical means foractuating said radial displacement means.
 19. A machine as claimed inclaim 1 wherein said means for folding and sealing said longitudinalopposed marginal flaps along said second web to the outer side edges ofthe U-shaped sections of said first web comprises flap folding members,reciprocating means for closing said flap folding members about theflaps and moving said flap folding members with said webs during sealingthereof and for subsequently returning said flap folding means to itsinitial position.
 20. A machine as claimed in claim 19 and furthercomprising means for heating the longitudinal edge surfaces of thelongitudinal opposed marginal flaps of the second web for heat sealingsaid flaps to the outer side edges of the U-shaped sections of the firstweb when folded by said flap folding means.
 21. A machine as claimed inclaim 20 wherein said heating means and said flap folding members arereciprocable together.